The proposed research is to conduct fundamental studies on the changes that occur in human milk and colostrum subjected to different processing methods and storage conditions used in milk bank operations. The research will include investigations of the microbial safety and nutritional efficacy of milk treated by thermal and non-thermal methods and will focus on changes that occur in the physical and chemical state of individual milk components. A model system simulating the electrolyte environment of human milk will be designed to aid in processing studies. The effect of thermal processing methods on the ultrastructure of human milk will be explored by electron microscopy. Immunoelectrophoretic techniques will be employed to determine quantitatively ongoing changes in individuals milk proteins. Specific antisera will be prepared for use in immunoelectrophoresis. The activity of milk cells (leucocytes, lymphocytes, macrophages) after processing treatments will be assessed by standard techniques and by microscopy. Heat-induced changes in N-acetylhexosamines and their derivatives will be quantitatively assessed by spectrophotometric analysis. Growth stimulation of bifidum organisms will be correlated with fecal flora from clinical studies. Non-thermal methods for preserving human milk for extended storage will be explored and will include approaches based on H2O2/catalase treatment in combination with subsequent culturing of the treated products with desirable microorganisms. Criteria for standardization of pooled human milk (and possible fortification) for milk bank operation will be established. Clinical studies will be conducted in collaboration with the Pediatric Nutrition Department at this University.